Biomedical subjects

T Tabata

Publications and source records attributed to T Tabata.

At least 73 records · Page 4Linked to original sources

PubMed1999

Clinical implications of coinfection with a novel DNA virus (TTV) in hepatitis C virus carriers on maintenance hemodialysis.

A novel hepatitis-associated DNA virus, designated as transfusion-transmitted virus (TTV), was identified recently. We investigated the frequency of TTV viremia in hepatitis C virus (HCV) carriers on maintenance hemodialysis to determine whether TTV coinfection has any clinical relevance. The subjects were 50 hemodialysis patients who had been followed over 4 years after diagnosis of HCV infection. Stored serum samples derived from each patient every 12th month after enrollment were subjected to polymerase chain reaction to amplify TTV DNA and HCV RNA. At enrollment, TTV viremia was detected in 24 (48%) HCV-positive patients irrespective of the number of previous blood transfusions and the duration of hemodialysis. The presence of TTV viremia had no relation to serum alanine aminotransferase (ALT) levels, HCV viremic levels or HCV genotypes. After enrollment, HCV infection persisted in all patients over the 4-year follow-up period, whereas spontaneous resolution of TTV infection was observed in 7 (29%) of the 24 TTV viremic cases (annual rate 7.3%, 95% confidence interval [CI] 0.8-25.5%). Evidence for TTV infection was found in 4 (15%) of the 26 TTV nonviremic patients (annual incidence 3.9%, 95% CI 0.1-19. 6%). The relationship between the ALT profile and TTV infection during follow up was not evident. Active TTV coinfection occurs frequently in HCV carriers undergoing hemodialysis but exerts no biochemical or virological influence on the underlying hepatitis C. Lack of disease association and the frequent spontaneous resolution of infection suggest that the clinical significance of TTV infection remains unclear.

Adult↗

PubMed1999

Assessment of the revised International Federation of Gynecology and obstetrics staging for early invasive squamous cervical cancer.

OBJECTIVE: The aim of this study was to investigate the value of the International Federation of Obstetrics and Gynecology (FIGO) classification (1995) for early invasive cervical cancer. Methods. Clinico-pathological analysis was performed in 402 patients with invasive squamous cervical cancer in whom the depth of stromal invasion was 5 mm or less. RESULTS: The incidence of lymph node metastasis was 1.2% (1/82) in patients with 3 mm or less depth of invasion; the node-positive patient was in stage IA1. The incidence of lymph node metastasis was 6.8% (5/73) in patients with 3-5 mm depth of invasion; this increased with increasing horizontal spread from 3.4% for 7 mm or less to 9.1% for more than 7 mm. None of the patients in this series had metastasis to the parametrial tissues. Of 4 patients with recurrence, 3 had horizontal spread of more than 7 mm and the remaining patient was in stage IA2. CONCLUSION: The FIGO definition of early squamous cervical cancer is generally acceptable in its present form.

Adult↗

PubMed1999

Low-grade endometrial stromal sarcoma with cardiovascular involvement--a report of three cases.

BACKGROUND: In low-grade endometrial stromal sarcoma, it has been reported that vascular space involvement in surgical specimens is found in over 50% of patients. However, in contrast to intravenous leiomyomatosis, it has been thought that further tumor extension to large vessels is rarely observed. CASES: We present three cases of low-grade endometrial stromal sarcoma with cardiovascular involvement by recurrent tumors observed on imaging studies. Two cases demonstrated tumor infiltration inside the inferior vena cava while the other case showed tumor growth in the left ventricle. CONCLUSION: This report suggests that attention should be paid to the possibility of cardiovascular invasion during the entire course of this disease.

Adult↗

PubMed1999

Functional evaluations for pulmonary resection for lung cancer in octogenarians. Investigation from postoperative complications.

We have reviewed the records of our twenty-four patients aged 80 years or older who underwent lung resections for bronchogenic carcinoma between 1983 and 1997 in our department. Eighteen patients were male and six were female. Adenocarcinoma was the histology in more than half of the cases (13 patients), along with 8 squamous cell carcinoma, 2 large cell carcinoma, and one small cell lung carcinoma. More than single lobectomy was performed in each patient. Unilateral pulmonary occlusion tests were employed in patients with impairment in pulmonary functions. Every patient, who underwent the unilateral pulmonary occlusion test, was certified that the total pulmonary vascular resistance index during unilateral pulmonary arterial occlusion test was less than 700 dyne.sec.cm-5.m2. Postoperative cardiovascular complications, such as paroxysmal atrial tachycardia, premature atrial contraction, premature ventricular contraction or atrial fibrillation, were seen in 10 patients. Postoperative respiratory complications, namely, sputa retention, retained secretions or atelectasis, were seen in 7 patients. The extent of dissection of mediastinal lymph node was not correlated to the postoperative pulmonary complications. However, the incidence of arrhythmias in the patients who received R2 mediastinal lymphnode dissection was much higher than in those who received R1 or R0 dissection. Complete blood counts and serum biochemical analysis performed at about three weeks after operations revealed leukocytosis and increases in levels of serum transaminase. These phenomena in leukocytosis and increases in the levels of serum transaminase in these patients were similar to those in younger patients. There was no operative death. We conclude that some patients over 80 years are candidates for lung resection after careful preoperative cardiopulmonary evaluation.

Adenocarcinoma↗

PubMed1999

Th2 subset dominance among peripheral blood T lymphocytes in patients with digestive cancers.

BACKGROUND: Two types of helper T cells (Th), which are categorized as Th1 and Th2 on the basis of cytokine production, have been reported. Th1 cells produce interleukin (IL)-2 and interferon (IFN)-gamma, while Th2 cells secrete IL-4, IL-6, and IL-10. We assessed the intracellular cytokine profiles of CD3/CD4 positive lymphocytes (CD4+ T-cells) in peripheral blood in patients with digestive cancers. METHODS: Peripheral blood samples were collected from 50 patients with digestive cancers and 35 healthy volunteers. The proportions of CD4+ T-cells producing intracellular cytokines were determined using flow cytometry. RESULTS: The percentages (mean +/- SD) of CD4+ T-cells producing IL-4, IL-6, and IL-10 in the cancer group (73.9% +/- 13.0%, 73.0% +/- 16.6%, and 58.0% +/- 21.0%, respectively) were significantly higher than in the healthy group (37.4% +/- 12.4%, 37.8% +/- 13.5%, and 34.0% +/- 14.1%, respectively; P <0.01). Proportions of CD4+ T-cells producing IL-4, IL-6, and IL-10 in 10 patients undergoing curative resection had decreased significantly 1 month after surgery (P <0.01). No significant difference was noted between groups in the percentages of CD4+ T-cells producing IFN-gamma. CONCLUSIONS: Th2-dominant status develops in cancer patients. Such lymphocyte evaluations could find applications in diagnosis and therapeutic monitoring of cancer patients.

Adult↗

PubMed1999

Leptin in peritoneal dialysate from continuous ambulatory peritoneal dialysis patients.

The adipocyte-derived hormone leptin is the 16-kd product of the ob gene that regulates food intake and body weight. Plasma leptin level is elevated in patients with chronic renal failure, partly because of impaired clearance through the kidney. In this study, we examined whether leptin is cleared into peritoneal dialysate in patients with end-stage renal disease treated by continuous ambulatory peritoneal dialysis (CAPD). The subjects were 46 CAPD patients and 67 age- and gender-matched healthy subjects. Leptin concentration in peritoneal dialysate from CAPD patients was measurable by a sensitive enzyme-linked immunosorbent assay (ELISA), and the daily loss of leptin by the peritoneal route was estimated to correspond to the amount contained in approximately 2 L plasma. Dialysate leptin concentration correlated positively with plasma leptin level and with percent body fat measured by dual-energy X-ray absorptiometry. The dialysate-to-plasma (D/P) ratio of leptin concentration was twice higher than expected from its molecular weight. D/P ratios of beta2-microglobulin, albumin, and transferrin showed strong correlations with each other (r = 0.768 to 0.801), whereas the correlation between D/P ratios of leptin and beta2-microglobulin was less impressive (r = 0.378). This was also the case with the relationship between apparent peritoneal clearances of these macromolecules, suggesting that dialysate leptin had some origins other than passive transport of plasma leptin. To test the hypothesis that abdominal visceral fat may contribute to the unexpectedly raised peritoneal dialysate leptin concentration, multiple regression analysis was performed. Leptin concentration in peritoneal dialysate showed significant association with plasma leptin level and D/P ratio of beta2-microglobulin, and it also showed an independent association with abdominal visceral fat but not with subcutaneous fat assessed by ultrasonography. These results showed that peritoneal dialysate from CAPD patients contained a significant amount of leptin, which derived presumably from both plasma and local visceral fat tissue.

Adipose Tissue↗

PubMed1999

Effect of aging on diastolic left ventricular myocardial velocities measured by pulsed tissue Doppler imaging in healthy subjects.

We evaluated the effect of aging on diastolic left ventricular (LV) wall motion velocity in 80 healthy persons with the use of pulsed tissue Doppler imaging. The wall motion velocity patterns were recorded at the middle regions of the LV posterior wall and ventricular septum in the parasternal (along the short axis) and apical (along the long axis) LV long-axis views. In the posterior wall, the peak early diastolic wall motion velocities (Ews) along both axes correlated inversely with age (long axis: r = -0.61, P <. 0001; short axis: r = -0.55, P <.0001), and the peak atrial systolic wall motion velocities(Aws) along both axes correlated directly with age (long axis: r = 0.59, P <.0001; short axis: r = 0.65, P <.0001). In the ventricular septum, the Ew along the long axis correlated inversely with age (r = -0.51, P <.0001), and the Aws along both axes correlated directly with age (long axis: r = 0.57, P <.0001; short axis: r = 0.53, P <.0001). The Ews along both axes at the posterior wall correlated directly with the peak early diastolic transmitral flow velocity. The Aws along both axes at the ventricular septum and posterior wall correlated directly with the peak atrial systolic transmitral flow velocity. The times from the second heart sound to the peak of the early diastolic waves of the ventricular septum and posterior wall along both axes significantly increased with age. The times from the aortic component of the second heart sound to the peak of the early diastolic motion velocities along both axes were significantly longer at the ventricular septum than at the posterior wall. Pulsed tissue Doppler imaging may be useful for evaluating the effect of aging on diastolic LV function in healthy persons.

Aging↗

PubMed1999

Pulsed tissue Doppler imaging of left ventricular systolic and diastolic wall motion velocities to evaluate differences between long and short axes in healthy subjects.

Our objective was to evaluate in healthy subjects the left ventricular (LV) wall motion velocities along the long and short axes by means of pulsed tissue Doppler imaging (TDI) to clarify the differences in the LV systolic and diastolic function between both axes. Wall motion velocities were recorded at the mid-wall portion of the middle site of the LV posterior wall in the parasternal long-axis view, and at the subendocardial portion of the middle site of the LV posterior wall in the apical long-axis view by pulsed TDI in 35 healthy subjects (mean age 26 +/- 10 years, mean heart rate 72 +/- 7 bpm). In all subjects, the LV pressure curve, its first derivative (dP/dt), the LV wall motion velocity, the phonocardiogram, and the electrocardiogram were simultaneously recorded. The systolic wave of the LV posterior wall motion velocity exhibited 2 peaks: the first and second systolic waves (Swl and Sw2, respectively). The diastolic wave also exhibited 2 peaks, the early diastolic and atrial systolic waves. The Swl along the long axis was greater than either the Sw1 and Sw2 along the short axis or the Sw2 along the long axis. The peak Sw1 along the long axis coincided with the peak dP/dt and was slightly earlier than the peak Swl along the short axis. The onset of Sw1 along the long axis coincided with the onset of the first heart sound. The Sw2 along the short axis was greater than that along the long axis. The early diastolic wave along the short axis was greater than that along the long axis, whereas the atrial systolic wave along the long axis was greater than that along the short axis. Thus, in healthy subjects, shortening of the longitudinal fibers predominated over that of the circumferential fibers during early systole, whereas shortening of the circumferential fibers predominated over the longitudinal fibers during the ejection phase. During diastole, the circumferential fibers predominated in the LV wall expansion at early diastole, whereas the longitudinal fibers predominated at atrial systole. In conclusion, pulsed TDI provided information that is useful in understanding the characteristics of LV wall motion along the long and short axes.

Adult↗

PubMed1999

Effect of an acute increase in afterload on left ventricular regional wall motion velocity in healthy subjects.

We recorded left ventricular (LV) wall motion velocities before and after angiotensin II infusion by pulsed tissue Doppler imaging in 20 healthy subjects, and evaluated the responses of systolic and diastolic LV function along the long and short axes during an acute increase in afterload. Angiotensin II was administered intravenously to obtain a 30% increase in mean blood pressure. After angiotensin II infusion, LV end-systolic dimension and end-systolic circumferential wall stress increased significantly, and the percentage of LV fractional shortening decreased significantly. Peak first systolic LV wall motion velocity (Sw1 ) along the long axis decreased markedly compared with that along the short axis, and peak second systolic LV wall motion velocity (Sw2 ) along the short axis decreased significantly compared with that along the long axis. Early diastolic LV wall motion velocities along both the long and short axes decreased significantly, whereas atrial systolic LV wall motion velocity did not change. In conclusion, an acute increase in afterload caused a significant decrease in longitudinal fiber shortening during the isovolumic contraction phase (Sw1 along the long axis), circumferential fiber shortening during the ejection phase (Sw2 along the short axis), and LV relaxation during early diastole (early diastolic LV wall motion velocities along both axes) in healthy subjects. Pulsed tissue Doppler imaging may be useful for detecting the effect of various loading conditions on LV wall motion velocities along the long and short axes.

Adult↗

PubMed1999

Left ventricular systolic wall motion velocities along the long and short axes measured by pulsed tissue Doppler imaging in patients with atrial fibrillation.

Pulsed tissue Doppler imaging was performed to measure systolic left ventricular (LV) posterior wall motion velocity along the long and short axes and to evaluate the relationships between the systolic variables and the maximum first derivative (peak dP/dt) of the LV pressure curve and the 2 preceding R-R intervals in 39 patients with atrial fibrillation (AF). The study group consisted of 22 patients with AF only, 17 patients with dilated or ischemic cardiomyopathy and AF, and 25 healthy control subjects in sinus rhythm. The systolic component of the LV posterior wall motion velocity was divided into the first (Sw1) and second (Sw2 ) systolic waves. The peak Sw1 along the long axis was greater than either that along the short axis or the peak Sw2s along the long and short axes in the control and AF-only groups. The peak Sw1 along the long axis was lower in the AF-only group than in the control group, and those along the short and long axes were lower in the dilated AF group than in the other groups. The peak Sw1 almost coincided with the peak dP/dt. The peak Sw1 along the long axis correlated closely with the peak dP/dt, and the ratio of the preceding R-R interval to the interval before the preceding ("prepreceding") R-R interval in both AF groups, particularly in the dilated AF group, and the slopes of their relationships were steeper in the dilated AF group than in the AF-only group. The peak Sw2 along the short axis was greater than that along the long axis in the control and AF-only groups. The peak Sw2 along the long axis was lower in the AF-only group than in the control group, and those along the short and long axes were lower in the dilated AF group than in the other groups. The peak dP/dt was lower and the LV end-diastolic pressure was higher in the dilated AF group than in the other groups. In conclusion, peak Sw1 along the long axis is useful for the evaluation of isovolumic myocardial LV contractility, and the interval-force relation and the Frank-Starling mechanism are important factors of beat-to-beat variability in systolic LV function in patients with AF.

Atrial Fibrillation↗

PubMed1999

Influence of aging on systolic left ventricular wall motion velocities along the long and short axes in clinically normal patients determined by pulsed tissue doppler imaging.

Our objective was to evaluate the influence of aging on left ventricular (LV) regional systolic function along the long and short axes in clinically normal patients. We recorded LV wall motion velocity patterns at the mid-wall portion of the middle of the LV posterior wall in the parasternal long-axis view (short-axis direction) and at the endocardial portion of the middle of the LV posterior wall in the apical long-axis view (long-axis direction) with pulsed tissue Doppler imaging in 80 normal patients (age range 15 to 78 years). In all patients the LV pressure curve and its first derivative (dP/dt) were recorded. The systolic wave of the LV posterior wall motion velocity pattern exhibited 2 peaks, the first (Sw(1)) and second (Sw(2)) systolic waves. No significant changes were seen with aging in the percent LV fractional shortening determined by M-mode echocardiography, LV ejection fraction determined by left ventriculography, the peak Sw(1) and Sw(2) along the short axis, the peak Sw(2) along the long axis, and the peak dP/dt. The peak Sw(1) along the long axis correlated inversely with age (P <.0001) but did not correlate significantly with the peak dP/dt. These results suggest that shortening of the longitudinal fibers in early systole is impaired with increased age in healthy individuals. This impairment results in insufficient spherical change in the LV cavity, although global LV pump function and myocardial contractility are maintained.

Adolescent↗

PubMed1999

Difference in the diastolic left ventricular wall motion velocities between aortic and mitral regurgitation by pulsed tissue Doppler imaging.

We evaluated the difference in the diastolic left ventricular (LV) wall motion velocity between chronic isolated aortic and mitral regurgitation (AR and MR, respectively) by recording subendocardial motion velocity patterns at the middle site of the LV posterior wall in the parasternal (along the short axis) and apical (along the long axis) long-axis views of the left ventricle with pulsed tissue Doppler imaging. We studied 33 patients with AR and 35 with MR, showing moderate to severe regurgitation, and 34 healthy controls (C). The end-diastolic LV dimension along the short axis was greater in the AR and MR groups than in the C group, and that along the long axis was greater in the AR group than in the MR and C groups. There were no significant differences in percent LV fractional shortening along the short axis among the 3 groups, whereas that along the long axis was significantly smaller in the AR group than in the MR and C groups. The peak early diastolic wall motion velocity (Ew) and the time to Ew from the aortic component of the second heart sound (S2 -Ew) along the long axis were significantly lower and longer, respectively, in patients with AR than in the 2 other groups. The Ew and S2 -Ew along both the short and long axes were significantly higher and shorter, respectively, in patients with MR than in the 2 other groups. The peak early diastolic velocity of the transmitral flow correlated positively with Ew along the short axis in all patients with AR and correlated positively with Ews along the long and short axes in all patients with MR. In conclusion, early diastolic LV filling was associated with expansion of the LV wall along the short axis but with decreased excursion along the long axis in patients with AR, whereas that in patients with MR was associated with expansion of the LV wall along both the long and short axes. Pulsed tissue Doppler imaging was useful for evaluation of diastolic LV function along the long and short axes in patients with diastolic LV volume overload.

Adult↗

PubMed1999

Identification and characterization of E-APC, a novel Drosophila homologue of the tumour suppressor APC.

BACKGROUND: Mutations in the adenomatous polyposis coli (APC) tumour suppressor gene are implicated in the genesis of colorectal cancers. The product of the APC gene forms a complex with beta-catenin, glycogen synthase kinase 3beta (GSK-3beta) and Axin/conductin, and induces the degradation of beta-catenin. RESULTS: We have identified a novel Drosophila homologue of APC, E-APC, which is similar to but differs in several respects from D-APC. The E-APC cDNA encodes a protein of predicted 1067 amino acids, with seven armadillo repeats, two copies of the 15-amino acid repeat, five copies of the 20-amino acid repeat, and one Axin/conductin binding site. E-APC directly interacts with D-Axin and Armadillo (Arm, the Drosophila homologue of beta-catenin) in vitro, destabilizes intracellular beta-catenin, and suppresses beta-catenin/TCF-regulated transcription in APC-/- colon cancer cells. The E-APC mRNA is ubiquitously expressed throughout all developmental stages in Drosophila. CONCLUSION: Our findings suggest that E-APC may be universally involved in the regulation of the Wingless signalling pathway by down-regulating the level of Arm in Drosophila.

Adaptor Proteins, Signal Transducing↗

PubMed1999

Effects of lipid-lowering drugs on intermediate-density lipoprotein in uremic patients.

BACKGROUND: Patients with chronic renal failure often have alterations in lipoprotein profile including elevated very-low density lipoprotein (VLDL) and intermediate density lipoprotein (IDL), and reduced high density lipoprotein (HDL) levels. Among these changes, raised IDL has been shown as an independent risk factor for atherosclerosis in hemodialysis patients. There are a limited number of studies reporting pharmacological approaches to IDL reduction in a uremic population. METHODS: We therefore summarize the effects of lipid-lowering drugs on IDL levels in patients with chronic renal failure treated by hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD). RESULTS: First, a nicotinic acid analog niceritrol was given to hemodialysis patients. The drug increased HDL-cholesterol by 11%, but the reductions in VLDL-, IDL- and LDL-cholesterol were not significant. Second, CAPD patients were treated with a fibric acid derivative clinofibrate, which was excreted mainly into bile unlike other drugs in this class. The fibrate resulted in a remarkable reduction in VLDL-triglycerides, although it did not reduce IDL-cholesterol. Finally, an HMG-CoA reductase inhibitor (statin) pravastatin was used in HD and CAPD patients. Pravastatin reduced IDL- and LDL-cholesterol to the same extent (by 31%). None of these treatments caused serious adverse effects. CONCLUSIONS: We propose that IDL is an important target in the management of uremic dyslipidemia. To date, statins have been shown to be suitable for this purpose, although it remains to be clarified whether such an intervention reduces the risk for atherosclerotic vascular events in the uremic population.

Cholesterol, LDL↗

PubMed1999

Coronary flow velocity immediately after reperfusion reflects myocardial microcirculation in canine models of acute myocardial infarction.

Recent reports indicate that the coronary microcirculation is sometimes injured, despite successful reperfusion in acute myocardial infarction (AMI). However, it is difficult to evaluate the coronary microcirculation immediately after reperfusion by using only angiography. The purpose of this study was to examine the relationship between the pattern of coronary blood flow velocity and myocardial microcirculatory injury immediately after reperfusion in AMI. The authors recorded the left circumflex coronary flow velocity by using the Doppler guide wire method 10 minutes after reperfusion in a canine model of AMI. In addition, myocardial contrast echocardiography was performed with the injection of contrast medium into the left circumflex coronary artery before clamping of the coronary artery and 15 minutes after release of the clamp. From these images, the ratio of the normalized gray-level postreperfusion to preclamping in the contrast-enhanced area was determined. It was compared with coronary flow velocity variables. In the 10 dogs with a diastolic-to-systolic velocity ratio (DSVR) < 4.0, this velocity ratio 10 minutes after reperfusion correlated positively (r = 0.75, p < 0.01) with the normalized gray-level ratio. However, the remaining three dogs with a DSVR > or = 4.0 markedly deviated from this pattern. Coronary flow velocities in the three dogs were characterized by a greater decrease in systolic flow velocity and occurrence of early systolic retrograde flow. Myocardial contrast echocardiographic images in these three dogs demonstrated a lower normalized gray-level ratio. In conclusion, the coronary flow velocity pattern immediately after reperfusion may reflect myocardial microcirculatory injury.

Albumins↗

PubMed1999

Possible involvement of histamine in muscular fatigue in temporomandibular disorders: animal and human studies.

As an approach to clarifying the molecular basis of pain and fatigue in muscles involved in temporomandibular disorders, we examined the activity of histidine decarboxylase (HDC), the enzyme which forms histamine, in the masseter muscles of mice. In the resting muscle, HDC activity was very low. Direct electrical stimulation of the muscle markedly elevated HDC activity. HDC activity rose within 3 hrs of the electrical stimulation, peaked at 6 to 8 hrs, and then gradually declined. Intraperitoneal injection of a small amount of interleukin-1 (IL-1) (from 1 to 10 microg/kg) produced a similar elevation of HDC activity in the masseter muscle. We also examined the effect of an antihistamine, chlorphenylamine (CP), on temporomandibular disorders in humans and compared it with that of an anti-inflammatory analgesic, flurbiprofen (FB). Two groups received one or the other of the drugs daily for 7 days, and they were asked about their signs and symptoms before and after the treatment. A positive evaluation of their treatment was made by 74% of the CP group, but by only 48% of the FB group. Although the effects of CP on the limitation of mouth-opening and on joint noise were negligible, about 50% of the CP group answered positively concerning the drug's effect on spontaneous pain or pain induced by chewing or mouth-opening. The positive evaluation for CP (50%) in relieving associated symptoms (headache or shoulder stiffness) was significantly greater than for FB (13%). FB showed effectiveness similar to but sometimes weaker than that of CP on several symptoms. On the basis of these and previous results and the known actions of histamine, we propose that the histamine newly formed following the induction of HDC activity, which is itself mediated by IL-1, may be involved in inducing pain and, possibly, stiffness in muscles in temporomandibular disorders.

Adult↗

PubMed1999

Assessment of the temporal relationship between left ventricular relaxation and filling during early diastole using pulsed Doppler echocardiography and tissue Doppler imaging.

The study investigated the temporal relationship between left ventricular (LV) relaxation and filling during early diastole. The transmitral flow (TMF) velocity by pulsed Doppler echocardiography and LV wall motion velocity by pulsed tissue Doppler imaging (TDI) were evaluated in 57 patients with various heart diseases and 33 normal controls. The patients were classified into 2 groups according to the ratio of the peak early diastolic to atrial systolic TMF velocity (E/A): (1) the high A group included 44 patients with an E/A < or = 1, and (2) the pseudonormalization group included 13 patients with an E/A > 1. The isovolumic relaxation time (IRT) from the aortic component of the second heart sound (IIA) to the onset of the E wave of the TMF was measured. The peak early diastolic velocity of the LV posterior wall (Ew) and time from the IIA to the onset of the early diastolic wave (IIA-Ewo) were determined from the LV wall motion velocity assessed by pulsed TDI. The Ew was lower in the pseudonormalization and high A groups than in the control group. The IIA-Ewo was significantly longer in the pseudonormalization and high A groups than in the control group. The time constant of the LV pressure decay at isovolumic diastole (tau) correlated negatively with the Ew, and correlated positively with the IIA-Ewo in all groups. The IIA-Ewo was equal to or shorter than the IRT in control subjects, and was longer than the IRT in patients in the pseudonormalization group. In conclusion, the temporal relationship between LV relaxation and filling during early diastole varied according to the subjects' hemodynamic status. Analysis of TMF by pulsed Doppler echocardiography and LV wall motion velocity by pulsed TDI was useful for detailed evaluation of early diastolic LV hemodynamics.

Blood Flow Velocity↗

PubMed1999

Regional left ventricular myocardial contraction abnormalities and asynchrony in patients with hypertrophic cardiomyopathy evaluated by magnetic resonance spatial modulation of magnetization myocardial tagging.

Global left ventricular (LV) pump function is generally preserved in patients with hypertrophic cardiomyopathy (HCM). However, it is unknown whether regional myocardial contractility is impaired, especially in nonhypertrophied regions. The purpose of this study was to evaluate regional LV myocardial contraction in patients with HCM using magnetic resonance (MR) spatial modulation of magnetization (SPAMM) myocardial tagging. The study group comprised 20 patients with asymmetric septal hypertrophy (HCM group) and 16 age-matched normal patients (control group), and data were collected using transthoracic M-mode and 2-dimensional echocardiography, and MR SPAMM myocardial tagging. The systolic strain ratio, maximum systolic strain velocity, and time from end-diastole to maximum systolic strain (deltaT) in the anterior, ventricular septal, inferior and lateral regions for 2 LV short-axis sections at the levels of the chordae tendineae and papillary muscles were measured at 50-ms intervals by MR myocardial tagging. The end-diastolic anterior and ventricular septal wall thicknesses and LV mass index were significantly different between the HCM and control groups. The systolic strain ratio for all 4 walls, particularly the anterior and ventricular septal regions, was significantly lower in the HCM group. In the HCM group, the maximum systolic strain velocity was significantly lower and deltaT was significantly shorter for all 4 walls, particularly the anterior and ventricular septal regions. The standard deviation for the deltaT, calculated from the deltaT for the 8 regions of the 2 LV short-axis sections, was significantly greater in the HCM group. In conclusion, regional LV myocardial contraction is impaired in both hypertrophied and nonhypertrophied regions, and systolic LV wall asynchrony occurs in patients with HCM.

Adult↗